Pulsed vs. continuous laser cleaning: which one wins?

Contents:

Laser cleaning is becoming an increasingly popular method of removing rust, paint and other contaminants from various surfaces without the use of chemicals or abrasive materials. But when choosing between pulsed and continuous wave laser systems, which one is suitable for your task?In this article, we compare two Wattsan laser cleaning machines: the Wattsan CW Pro with a 3000W continuous laser source and the Wattsan PA with a 300W pulsed laser source. Despite the significant difference in power, both machines have unique advantages depending on the application. Through practical tests on various materials, we identify the advantages of each model, as well as possible disadvantages.

Rust removal

Rust is one of the most common problems in surface preparation. With its powerful continuous beam and dual mirror scanning system, Wattsan CW Pro is great for quickly cleaning large areas, especially with a thin layer of rust. However, due to the high heat transfer, there is a risk of overheating and deformation of the metal if the laser remains in one place for too long. Therefore, it is very important to constantly move the laser and carefully adjust the settings.

The Wattsan PA pulsed laser, on the contrary, removes rust more slowly, but does an excellent job with thermoregulation. Short, high-intensity pulses vaporize rust without heating the base material, making it ideal for delicate surfaces or tasks where it is important to maintain structural integrity.

Paint removal

We tested both systems on dried animal-based paint applied to metal. The continuous laser removed the paint, but generated a significant amount of heat, enough to ignite and form traces. On the other hand, the Wattsan PA pulse system removes paint cleanly, without overheating, thanks to concentrated energy emission. This makes a pulsed laser the best choice for removing paint, especially from sensitive or coated surfaces.

When applying powder coatings, the pulse system proves its superiority again. It ensures a clean coating, preparing the surface for immediate repainting with excellent adhesion.

Cleaning porous surfaces: stone, brick, and concrete

These materials often absorb paint deeply, making cleaning difficult. The pulsed laser effectively penetrates the pores of the surface without damaging the material itself, making it ideal for restoration work. On the contrary, a continuous laser, as a rule, removes the top layer of the material along with pollutants, which does not allow to preserve the surface details.

This is why pulsed lasers are widely used in urban cleaning and monument restoration, as well as for graffiti removal and post-fire cleaning. Their accuracy guarantees no damage to historical or delicate surfaces.

Soot, carbon, and plastics

When working with soot or carbon deposits, a continuous laser requires careful handling to avoid burns. The pulsed laser once again proves its versatility, allowing precise removal without leaving burn marks.

When working with plastics, a continuous laser significantly increases the risk of deformation or ignition. Pulse systems are much safer and better suited for this task, as they minimize thermal effects.

Wood and paper

The absorbency of wood can make cleaning difficult, especially if the paint has penetrated its fibers. Continuous lasers tend to burn or carbonize surfaces, while pulsed lasers can remove paint without significant scorching. Even more impressively, pulsed lasers can vaporize prints from paper, effectively bleaching it, which is impossible with continuous-action lasers.

Applications and use cases

To summarize:

• Wattsan CW Pro (1500-3000W continuous power): Best suited for large-scale industrial applications where speed is a priority and surface appearance is less important. Ideal for flat surfaces, quick rust removal and general cleaning.
• Wattsan PA (100-500W pulse power): Ideal for precision work such as restoration, thorough cleaning and work with sensitive materials. It easily handles denser contaminants, plastics, composites, and historical surfaces.

Both machines are equipped with Relfar laser guns, selected by Wattsan engineers for their durability, performance and operator convenience. Wattsan’s 20 years of experience in CNC machining, CO2 lasers, fiber cutters, welding machines, and cleaners ensures that each machine will operate efficiently and for a long time.

Conclusion

The choice between pulsed and continuous laser cleaning depends on the objectives of your project. If you need fast results on industrial-scale surfaces, choose a continuous-action system such as Wattsan CW Pro. But if you are working with delicate materials, detailed restorations, or multi-layered contaminants, it is best to use a pulsed laser such as Wattsan PA.

Each system has its own place. And having a suitable laser cleaner in your arsenal, you will achieve better results, speed up repairs and extend the service life of the equipment.

YouTube video